Hydraulic pump or motor



Dec. 15, 1953 R. ELLER HYDRAULIC PUMP OR MOTOR 12 SheetsSheet 1 Filed Dec. 19, 1949 I xii.

INVENTOR.

ATTORNEY Dec. 15, 1953 R. ELLER 12 Sheets-Sheet 2 INVENTOR.

ATTORNEY Dec. 15, 1953 R. ELLER 2,662,484

' HYDRAULIC PUMP OR MOTOR Filed Dec. 19, 1949 12 Sheets-Sheet 3 3 1 w 1 4 w a w m #1 Z m 8 WM 2 6 a E lu u \/4l. +1 I i fi\ m g E f I I Z? fi 5% W1 a \W\\ nmwafl w m 5 Z 7 0 5 Z w z a z s R. L. ELLER HYDRAULIC PUMP OR MOTOR Dec. 15, 1953 12 Sheets-Sheet 4 Filed Dec. 19, 1949 INVENTOR. @5221 L. Z6221 kw 4770/7/VEY Dec. 15, 1953 R. L. ELLER HYDRAULIC PUMP OR MOTOR 12 Sheets-Sheet 5 Filed Dec. 19, 1949 O VV ELLER Dec. 15 1953 Filed Dec. 19, 1949 INVENTOR, 2)? L Eb hw Arrow/5y Dec. 15, 1953 R. L. ELLER HYDRAULIC PUMP OR MOTOR l2 Sheets-Sheet 7 Filed Dec. 19, 1949 INVENTOR. 1 6522? ilk)" M fi/eflv ATTORNEY R. L. ELLER HYDRAULIC PUMP OR MOTOR Dec. 15, 1953 12 Sheets-Sheet 8 Filed Dec. 19, 1949 III/l INVENTOR. 166222 712 04% 477'0P/VEY Dec. 15, 1953 R. ELLER HYDRAULIC PUMP OR MOTOR 12 Sheets- Sheet 9 Filed Dec. 19, 1949 ATTOPA/EY Dec. 15, 1953 R. ELLER HYDRAULIC PUMP OR MOTOR l2 Sheets-Sheet 10 Filed Dec. 19, 1949 INVENTOR. @522? LEZZer 4 Tram/15y R. L. ELLER 2,662,484 7 l2 Sheets-Sheet ll INVENTOR.

ATTORNEY Dec. 15, 1953 R. ELLER 2,662,484

HYDRAULIC PUMP OR MOTOR Filed Dec. 19, 1949 12 Sheets-Sheet l2 IN V EN TOR.

By {0156); z. 550 w [044% ATTOP/VEY Patented Dec. 15, 1953 UNITED STATES rArsNr orrlcs 2,662,484 HYDRAULIC PUMP 0R MOTOR Robert L. Eller, Spokane, Wash. Application December 19, 1949, Serial No. 133,802 10 Claims. (01. 103-461) This invention relates to improvements in an hydraulic pump or motor.

A machine of this type will function as a pump when it is driven mechanically and it will function as a motor when it is supplied with motive liquid. In the following description the machine will be referred to as a pump but it is to be understood that the present invention is equally applicable when the machine is operated as 'a pump or as a motor.

Machines of this character embody a cylinder barrel which is provided with radial cylnders and pistons arranged within an annular thrust membar. When the cylinder barrel axis is offset from the axis of the thrust member relative rotation between the cylinder barrel and the thrust memher will cause the pump to pump liquid when the liquid inlet feeds into the cylinders as the pistons move outwardly'along the surface of the thrust member and the liquid outlet receives liquid from the cylinders when the pistons moveinwardly along the surface of the thrust member. It is a purpose of the present invention to provide a novel mechanism for controlling the offset of the cylinder barrel axis and the thrust member axis whereby to vary the liquid volume pumped, or in the case where the machine is used as a motor, to vary the speed of rotation between the cylinder barrel and the thrust member.

It is also a purpose of the invention to provide a novel bearing construction whereby the radial thrust of the pistons is distributed through a heating bearing member to the thrust member.

It is also a purpose of the invention to provide in a machine of this character a novel fluid inlet and outlet construction to the radial cylinders through the cylinder barrel whereby to effectively seal the inlet to the cylinder barrel and the outlet to the cylinder barrel connections without excessive pressures between the relatively moving parts, the construction being such that wear on the meeting surfaces is automatically taken up and the pressure seal is maintained.

My invention contemplates the provision in a machine of this character of a cylinder barrel having a series of radial cylinders with cap pistons thereon with axial inlets and outlets through the cylinder barrel and balanced valve units utilizing the eifective liquid pressure in the cylinder barrel passages to seal connection between I the inlet and outlet members and the cylinder barrel. The cap pistons carry rollers which run upon a thrust ring that is free to rotate within the thrust member and is supported within the thrust member by roller bearings. The thrust member itself embodies relatively rotatable cam rings operable to shift the axis of the thrust ring with respect to the cylinder barrel axis to vary the volume of liquid delivered at the outlet of the pump from zero to the maximum. The arrangement is such that the axis of the thrust ring can be moved to either side of the axis of the cylinder barrel through the axis of the cylinder barrel at which point the volume of liquid pumped is of course zero. The pump is thus reversible so that liquid may be taken from either end of the cylinder barrel and delivered to the other. Likewise when the machine is used as a motor and the motor fluid is fed into one end of the cylinder barrel the thrust member may be rotated in either direction from zero speed to the maximum speed.

My invention further contemplates a novel cam control mechanism whereby the cam rings may be moved together to cause the central axis of the thrust member to shift along a straight line through the axis of the cylinder barrel.

Other and more detailed objects and advantages will appear from the following description and the accompanying drawings wherein a preferred form of the invention is shown. The drawings and description are illustrative only, however, and should not be considered as limiting the invention except insofar as it is limited by the claims.

In the drawings:

Figure 1 is a View in side elevation of a pump embodying my invention;

Figure 2 is an end view of the pump;

Figure 3 is a sectional view taken on a vertical plane through the longitudinal axis of the pump with the ends broken away and the control mechanism left oil;

Figure 4 is a sectional view on a reduced scale taken on the line 44 of Figure 3;

Figure 5 is a fragmentary sectional view taken on the line 55 of Figure 3;

Figure 6 is a fragmentary sectional view taken on the line 6-6 of Figure 3;

Figure '7 is a sectional view like Figure 4, but showing the thrust member axis shifted with respect to the cylinder barrel axis, to a different position than that shown in Figure 4;

Figure 8 is an enlarged fragmentary sectional view taken on the line 23-43 of Figure 3;

Figure 9 is an enlarged fragmentary sectional view taken on the line 9-9 of Figure 4;

Figure 10 is a View partly in section and partly in elevation taken along the line lilli of Figure 1, with the cover of the control mechanism removed;

fragmentary sectional view on lI-ll of Figure 11 is a an enlarged scale taken along line Figure 2;

Figure 12 is an enlarged sectional view taken on the line 12-42 of Figure with the cover of the control mechanism in place;

Figure 13 is an enlarged fragmentary sectional view taken on the line l3-i3 of Figure 10;

Figure 14 is a fragmentary end view taken on the line 14-14 of Figure 1;

Figure 15 is a fragmentary sectional view taken on the line 15-45 of Figure 3 looking toward the end shown in Figure 14;

Figure 16 is a sectional view 16 -16 of Figure 1; and I Figure 17 is a sectional view on the curved line 11-11 of Figure 5.

Referring now in detail to the drawings and particularly to Figures 1 to 3 inclusive, and 14 to 11 inclusive, my invention is embodied in a pump wherein the numeral 20 indicates a base with supporting plates 2| and 22 secured thereon to mount a housing ring 23. is closed at its ends by two end plates 24 and 25. The plate 24 has a bearing boss 26 projecting laterally therefrom and provided with a recess for a packing ring 21 and another recess for a roller bearing ring 28. The packing ring is compressed by a series of screw bolts 23 against a sleeve 3!) which forms the driving member to which power is applied for operating the device as a pump. A washer 3i confines the roller bearing ring 28 in the recess provided in the end plate 24. The end plate has a flange 32 co-axial with the part 25 of the end plate 24. The end plates 24 and 25 are secured on the housing ring 23 by bolts 33 and 34 as indicated clearly in Figure 3.

Members providing fluid inlet and outlet channels to the pump are shown at 35 and 35. These members are secured on an axle 31 that extends taken on the line through the pump by means of caps 38 and 39 which are bolted to the axle 31. The member 35 is of shorter length wise they are essentially alike in construction. Figures 14, 15 and 16 illustrate the construction of these members. Each member has a laterally projecting coupling portion 40 which has two inlet channels 41 and 42 leading to a plurality ofapertures 43 and 44 that extend to the inner face of the member. The apertures 43 are in the member 35, and the apertures 44 are in the member 36. Each set of apertures is restricted to less than one half the circumference of the member in which the apertures are found. At the inner face of the member 35 all of the apertures '43 are joined by a channel 45. A like channel 46 joins the inner ends of the apertures 44. The channel 46 is illustrated best in Figure 15, which is a section'al view through the inner end of the member 36. It will be noted that the member 33 has a flange at 41 which abuts the drive sleeve 30. The members 35 and 38 are keyed to the axle 31 by keys 43. (See Figures 15 and 16.) The member 35 has a flange 43 that is bolted to the flange 32 of the end plate 25.

The axle 31, the ring 23 and the end plates 24 and 25 serve to mount and enclose the operating parts of the pump. These parts include a cylinder barrel 53 which is journalled by roller bearings 5i and 52 for rotation on the axle 31. The cylinder barrel has ports 53 extending from end to end thereof. One end of the barrel 5B is flanged at 54 and the flange is interlocked with This housing ring than the member 36, other- -51 communicating with the member 39 by slotting the flange and the end of the member 30 to form meshing teeth 55 and 56 so that the barrel 58 must rotate with the member 30. See Figures 3, 6, 9 and 1'1 of the drawings for this connection. The ports 53 are evenly spaced throughout the circumference of the barrel 50. The ports 53 are so arranged that no port is diametrically opposite another. As shown best in Figure 4 there are 13 of the ports 53, although of course, the number may be varied.

Referring now to Figures 3 to 6 inclusive and Figure 1'1, the details of the cylinders carried by the barrel 50, their pistons and the thrust members will be described. The barrel 50 serves to mount a plurality of radially extending cylinders each of the ports 53. A cap piston 58 fits over the outer end of each oi. the cylinders 51. Each piston has a pair of bearing mounting posts 59 and 60 formed integral therewith to receive rollers BI and 52. The rollers 51 and 82 are mounted on the posts 59 and 60 by needle roller bearings indicated at 63 and 64. The rollers 61 and '52 ride upon two rings -65 and 5B which are mounted in a free rotatable thrust member 61.

The thrust member 61 is made up of two parts 38 and T69 which are bolted together by bolts '13 (see Figure 3). The part .68 is an annular memher having a flange portion 1| of relatively small diameter and a rib portion 12 extending radially outward from the portion 1| and apertured with a series of small apertures 13-14 at intervals throughout its circumference. The portion 12 joins a circular portion 15 concentric and larger than the portion 11 .of the member and .extending from the opposite side of the portion 12. The part 59 of the thrust member 61 is bolted to the free edge of the portion 15 by the bolts 10. This part 63 has an annular flange 16 extending outwardly therefrom and opposite to the flange portion 11 of the member 68. A spacing band 11 is set into the portion 15 of the member 68 and laps over the ring 55 as shown in Figure 3. The ring 85 abuts the other edge of the band 11 and is held against this edge by the member 69. In this way the rings 55 and 6B and the member 51 form a free rotatable thrust member against which the rollers 61 and 52 on the several pistons 58 can press as the cylinder barrel 5B is rotated.

The small apertures '13 are utilized in separating the ring 65 from the member 61 when the parts are being disassembled. The aperture 13 permits insertion of a small tool to drive the ring 65 out.

The flanges 1| and 16 serve to support the inner races 18 and 19 for roller bearings and 8|. The inner race 18 can be driven off the flange 11 by inserting a tool through the aperture 14. Like apertures (not shown) are provided in the member'GQ for driving off the race 19 from the flange 16. Other races 82 and 83wfor the bearings 80 and BI bear against the inner faces of inner cam members 8-4 and 85. The cammembers 34 and 85 are joined rigidly by a web 86 and bolts 81. The thrust member 61 with its associated parts is thus supported for free rotation, by means of the bearings 88-81, in the annular cam composed of the members 84 and 85 and their connecting means. An outer cam 88 is rotatably seated in the housing ring 23 and has its inner bearing face supporting the inner annular cam B L-85.

The inner and outer cams just described form the means for shifting the axis of the thrust member 51 with respect to the center of the cylinder barrel 50 to vary the capacity of the pump or the rotation of the device when it is used as a motor. The details of how this shifting of the axis of the member 6'! is accomplished by the cams will be described more fully hereinafter. A comparison of Figures 4 and 7 will show the two difierent positions of the member 61 with respect to the axis of the cylinder barrel 59. Note that in Figure 4 the cams 84-85 and 89 are so positioned that the member 9! is raised with respect to the axis of the cylinder barrel 59 so that the pistons 58 at the bottom of the figure are moved inward on the cylinder substantially to their limit while the pistons 53 at the top of the figure have moved outward substantially to their limit. In Figure 7, the cams 8485 and 88 have been rotated so as to move the member Bl downwardly until the pistons 58 at the top of the figure are moved inward substantially to their limit and the pistons 58 at the bottom of the figure have moved outward a corresponding degree. It will be appreciated that through the intermediate positions of the cams the axial centers of the member 6? and the barrel 50 will vary from an extreme displacement in one direction through coincidence to extreme position in the other direction.

Figure 9 is a sectional view looking up on the line 99 of Figure 4 and illustrates how the liquid from the inlet openings 4I-42 to the ;r,'

member can flow in through the channel to the ports 53 at one side of the pump. This liquid will fill six of the cylinders at the left hand side of the vertical center line through Figure 4 and force the pistons on these cylinders out as they move upwardly as shown in Figure 4. The extreme top piston in Figure 4, is sealed off by virtue of the fact that its port 53 is between the slot 45 on the inner face of the member 35 and the slot 46 on the inner face of the member 35. As soon as the cylinder barrel 59 rotates far enough to bring the port 53 of this topmost piston into communication with the slot 46 of the member 36 an outlet will be provided through the openings 44 and the connections 4| and 42 for the liquid trapped in the cylinder and piston. The six cylinders and pistons on the right hand side of a vertical line through Figure 4, are thus discharging liquid as the pistons are being forced inward by contact of their rollers 6 I-B2 with the thrust rings and 66 in the member 67.

Figure 7 shows the reverse condition of that in Figure 4. When the cylinder barrel 59 rotates in the same direction as in Figure 4, liquid will be pumped in the opposite direction, that is, from the member 36 and its connections 4ll2 through the cylinder barrel and cylinders to the member 35 and its connections. The volume of liquid handled in either direction per rotation of the cylinder barrel will be a maximum at the maximum displacement of the axis of the memher 6! with respect to the axis of the cylinder barrel 50. As the cams 84-85 and 88 are shifted to bring these axes toward each other, the volume of liquid moved for each rotation of the cylinder barrel is reduced.

It will be noted that there is no means other than the friction of the roller bearings to prevent free rotation of the member 67. The thrust is thus distributed over a wide area and the speed of rotation of the member 61 may vary, depending upon the frictional resistance of the bearings from zero to a speed equal to that of the rotation of the cylinder barrel.

The mechanism by which the cams 94-85 and s 88 are shifted is illustrated best by Figures 1, 4, 7, 11, 12 and 13. A housing 99 is secured on the end plate 25 by suitable screw bolts indicated at 9| in Figure 10. This housing is Y-shaped with the extremities of the Y enclosing two connecting pins 92 and 93 which extend through slots 94 and 95 provided in the housing and like slots 96 and 97 are provided in the end plate 25. pin 92 is anchored in the inner cam member 84 while the pin 93 is anchored in the outer cam 88. A link 98 is pivoted on the pin 92 and a similar link 99 is pivoted on the pin 93. These two links are connected together by a pivot pin I00 that is mounted in a crosshead IN. The link 99 is bifurcated at its upper end and the link 99 is reduced in width so that both of them can be mounted in the U-shaped crosshead It! as illustrated in Figures 11 and 12. The crosshead is guided in the housing 99 by guide ribs I02 and I03. A piston red I [it is secured to the crosshead and extends through the upper end of the housing 50 into a cylinder 95. The cylinder N15 has a flanged lower end E96 that is secured on the housing and carries a packing gland I0? for the piston rod I 94 and threaded apertures I 98 for screws to tighten the packing. Suitable fluid connections are indicated at I99 and I ill for connecting a supply of motive fluid to the cylinder 595 to move a piston ill that is secured on the rod I94. It will be noted upon inspection of crosshead Illi is not radial with respect to the axle 31 and the housing ring 23. The direction of movement of this crosshead and the lengths of the links 98 and 99 are so calculated as to cause the correct proportional movements of the cams s t-ts and 88 for shifting the axis of the thrust member El along substantially a straight line through the axis of the axle 37. It will be appreciated that since the cam 88 is larger and thrust member 57.

One of the problems in a pump or motor of der barrel which must have a relatively rotatable movement with respect to these members. In the present device I have provided a novel cylinder barrel construction whereby the sealing at the faces which rotate with respect to each other is accomplished. Figures 3, 8 and 9 best illustrate this feature of my invention. The cylinder barrel 50 is provided with an extension tea at the end opposite its connection to the sleeve 39. This extension is coupled to the cylinder barrel by a series of nipples I I2 which extend into each of the ports 53. These nipples are recessed and the extension 59c are recessed to receive split rings II3 which abut the end face of the cylinder barrel 59 so as to limit the extent to which the nipple may enter the cylinder barrel. The enlargement of the port 53 to receive the nipple H2 is long enough to leave a space I I4 at the inner end of the nipple. A packing ring H5 is utilized to seal the joint between the nipple and the cylinder barrel against leakage.

In operation When the ports 53 are filled with liquid under pressure, this pressure communicates a certain force to the inner end of each nipple H2 which is exposed due to the space H4. This pressure tends to force the extension 59a away from the barrel and thus maintain a continuous pressure between the extension 56c and the inlet member 35 to prevent leakage between these relatively rotating faces. Thi pressure is likewise communicated to the relatively rotating faces of the member 35 and the cylinder barrel 56. As the faces wear the pressure spreads the cylinder barrel and the extension 59a apart to maintain a seal at the rotating faces. This pressure is, of course, only a fraction of the pressure which may exist in the ports -53 so that the rotating faces do not have to turn with respect to each other under the extremely high pressures developed by the pump or used in the motive liquid when the device operates as a motor. Sufficient clearance must be provided between the sleeve 3d and the end flange ll of the member 36 to permit take up of the wear between the member 35 and the cylinder barrel 5!). This clearance will normally develop by wear since the member 38 will tend to press endwise against the flange 4'1. In manufacture, I prefer to provide the cylinder barrel and its extension 59awith specially hardened faces where they engage the members 35 and 36 so as to limit the wear thereon and cause whatever wear that takes place to be largely on the members 35 and 3'5. It is then a simple matter to resurface the members 35 and 36 without the necessity of replacing the expensive cylinder barrel. With the construction provided, however, a longer lift is obtained because of the reduction of wear on the relatively rotating faces.

It is believed that the construction and operation of the present device will be clear from the foregoing description. Attention is called at this point to the fact that all of the parts are easily accessible so that any bearing or bearing surfaces may be inspected and checked without completely dismantling. The construction is such that the tremendous radial thrusts that are built up when the device is operated at high pressure are distributed over a maximum surface with ample strength radially of the machine to withstand the pressures developed.

Having thus described by invention, I claim:

1. In a machine of the character described, a cylinder barrel having outwardly extended cylinders circumferentially spaced about the barrel, pistons on said cylinders, bearings on said pistons, a freely rotatable circular thrust member encircling the bearings, annular cam means encircling and rotatably mounting the thrust member, a circular housing ring encircling the cam means, means mounting the barrel for rotation with respect to the ring about the axis of said ring, the cam means being shiftable circumferentially in said ring to move the axis of said thrust member toward and away from the axis of the cylinder barrel.

2. In a machine of the character described, a rotatable cylinder barrel having radially extended cylinders circumferentially spaced about the barrel, a fluid passage longitudinally through the barrel for each cylinder having an opening to the cylinder intermediate the ends of the barrel, pistons on said cylinders, bearings on said pistons, a circular thrust member encircling the bearings and having. its axis offset with respect to the barrel axis whereby rotation of the barrel moves the pistons in and out on their cylinders against the radial pressure of the fluid in the cylinders, fluid inlet and outlet members rotatably engaging the ends of said barrel and having oppositely disposed channels in their barrel engaging faces for fluid flow to and from the passages in the barrel, said barrel comprising two sections axially movable with respect to each other and means for causing the fluid pressure in said passages to urge said sections apart to maintain a sealing pressure between the barrel ends and the cooperating faces of the inlet and outlet members.

3. In a machine of the character described, a rotatable cylinder barrel having radially extended cylinders circumferentially spaced about the barrel, a fluid passage longitudinally through the barrel for each cylinder having an opening to the cylinder intermediate the ends of the barrel, pistons on said cylinders, bearings on said pistons, a circular thrust member encircling the bearings and having its axis offset with respect to the barrel axis whereby rotation of the barrel moves the pistons in and out on their cylinders against radial pressure of the fluid in the cylinders, fluid inlet and outlet members rotatably engaging the ends of said barrel and having oppositely disposed channels in their barrel engaging faces for fluid flow to and from the passages in the barrel, said barrel comprising two sections axially movable with respect to each other and nipples fixed to one section and extending into the other section and having exposed ends for causing the fluid pressure in said passages to urge said sections apart to maintain a sealing pressure between the barrel ends and the cooperating faces of the inlet and outlet members.

4. In an hydraulic motor or pump, an inner cylinder barrel, and. an outer ring concentric therewith, the barrel being rotatable relative to said ring, a circular thrust member within the ring, cylinders radiating from the barrel, pistons for said cylinders having bearings engaging the thrust member, an outer annular cam rotatably seated in said ring, an inner annular cammounted on the thrust member and seated in the outer cam, said cams being rotatably adjustable relative to each other to shift the thrust member in the ring in a radial direction with respect to the axis of the cylinder barrel for varying the amount of radial travel of the pistons on their cylinders.

5. In an hydraulic motor or pump, an inner cylinder barrel, and an outer ring concentric therewith, the barrel being rotatable relative to said ring, a circular thrust member within the ring, cylinders radiating from the barrel, pistons for said cylinders having bearings engaging the thrust member, an outer annular cam rotatably seated in said ring, an inner annular cam mounted on the thrust member and seated in the outer cam, said cams being rotatably adjustable relative to each other to shift the thrust member in the ring in a radial direction with respect to the axis of the cylinder barrel for varying the amount of radial travel of the pistons on their cylinders and bearings rotatably mounting the thrust member for rotation in said inner cam.

6. In an hydraulic motor or pump, an inner cylinder barrel, and an outer ring concentric therewith, the barrel being rotatable relative to said ring, a circular thrust member within the r1ng, cylinders radiating from the barrel, tubular p1stons telescoped over the cylinders, diametrically opposed rollers on each piston inwardly of the outer end of its cylinders, said thrust memher having inner bearing surfaces for the rollers and means in said ring rotatably mounting the thrust member for rotation on an axis offset from a of the ylinder barrel, said means comprising an outer annular cam journalled in th ring, and an inner annular cam carried by the outer cam in which the thrust member is journalled for rotation.

7. In an hydraulic motor or pump, an inner cylinder barrel, and an outer ring concentric therewith, the barrel being rotatable relative to said ring, a circular thrust member within the ring, cylinders radiating from the barrel, tubular pistons telescoped over the cylinders, diametrically opposed rollers on each piston inwardly of the outer end of its cylinders, said thrust member having inner bearing surfaces for the rollers and means in said rin rotatably mounting the thrust member for rotation on an axis offset from the axis of the cylinder barrel, said means comprising an outer annular cam journalled in the ring, and an inner annular cam carried by the outer cam in which the thrust member is journalled for rotation, a link attached to the outer cam, a second link attached to the inner cam, a cross-head supporting the links, and means to move the cross-head for causing relative rotation of said cams and consequent shifting of the thrust member axis with respect to the axis of the cylinder barrel.

8. In a machine of the character described, a cylinder barrel having radially extended cylinders circumferentially spaced about the barrel, a fluid passage longitudinally through the barrel for each cylinder having an opening to the cylinder intermediate the ends of the barrel, pistons on said cylinders, bearings on said pistons, a circular thrust member encircling the bearing and rotatable relative to the barrel on said bearings, said member having its axis oilset with respect to the barrel axis whereby rotation of the barrell moves the pistons in and out on their cylinders against radial pressure of fluid in the cylinders, fluid inlet and outlet members rotatably engaging the ends of said barrel and having oppositely disposed channels in their barrel engagin faces for fluid flow to and from the passages in the barrel, and an axle rotatably supporting the cylinder barrel, said inlet and outlet members being mounted on said axle.

9. In a machine of the character described, a

a fluid passage longitudinally through the barrel for each cylinder having an opening to the cylinder intermediate the ends of the barrel, pistons on said cylinders, bearings on said pistons, a circular thrust member encircling the bearing and rotatable relative to the barrel on said bearings, said member having its axis offset with respect to the barrel axis whereby rotation of the barrel moves the pistons in and out on their cylinders against radial pressure of fluid in the cylinders, fluid inlet and outlet members rotatably engaging the ends of said barrel and having oppositely disposed channels in their barrel engaging faces for fluid flow to and from the passages in the barrel, an axle rotatably supporting said barrel, said fluid inlet and outlet members being mounted on the axle at the ends of said barrel, and a drive member for said barrel comprising a sleeve fixed to the barrel and rotatable on one of said inlet and outlet members.

10. In an hydraulic motor or pump, an inner cylinder barrel, an outer ring concentric therewith, an axle supporting the barrel for rotation relative to said ring, cylinders radiating from the barrel, a fluid passage longitudinally through the barrel for each cylinder having an opening to the cylinder intermediate the ends of the bara circular thrust member within the ring,

cylinders having bearings engaging the thrust member, fluid inlet and outlet members rotatably engaging the ends of said barrel and mounted on said axle, said members having oppositely disposed channels in their barrel engaging faces for fluid flow to and from the passages in the barrel, and plates for said ring, said inlet and outlet members extending through the end plates, annular cam members, one within the other in said ring encircling and rotatably mounting the thrust member in the ring and means to turn one cam member with respect to the other to move the axis of the thrust member toward and away from the axis of the cylinder barrel.

ROBERT L. EILER.

References Cited in the file of this patent UNITED STATES PATENTS 

